Just odd......

So my husband and I had unprotected sex about a month ago. Last week I started feeling light headed and getting real nauseous over small smells. I've taken two tests and both negative. But the symptoms are still there. I'm peeing more often with no change in my fluid intake and I'm always light headed and nauseous. Ive recently been tired all throughout the day but have not changed my routine at all. Any inputs?!?!??